This invention relates to a process for polymerizing olefins. In another aspect, this invention relates to a process for making a polymerization catalyst. In another aspect, this invention relates to a process for polymerizing alpha-olefins using a catalyst system wherein said catalyst is prepared by a novel process. In another aspect, this invention relates to a novel process for forming a catalyst which can be used with a co-catalyst to form a catalyst system for the polymerization of alpha-olefins. In another aspect, this invention relates to a catalyst prepared by mixing a milled mixture of magnesium and an inorganic solid with an alcohol and then contacting said product mixture with a titanium compound. In another aspect, this invention relates to a catalyst system for polymerizing alpha-olefins wherein a first component, obtained by mixing a milled mixture of magnesium and an inorganic solid with an alcohol and then contacting the resultant product with a titanium compound, is combined with a second component comprising an organometallic compound, e.g., an organoaluminum compound.
It is known to polymerize alpha-olefins and mixtures thereof according to the low pressure process of Ziegler. In this process, the catalysts used are prepared from mixtures of compounds of elements of Subgroups IV to VI of the Periodic Table and the organometallic compounds of the elements of Groups I to III of the Periodic Table. The polymerization is generally carried out in suspension, in solution or even in a gaseous phase.
The activity of an olefin polymerization catalyst is one important factor in the continuous search for a catalyst useful for the polymerization of alpha-olefins. It is also desirable that the process used in forming the catalyst be such as to allow ease in preparation and to allow control over the final catalyst formed.
It is an object of this invention, therefore, to provide an improved process for the polymerization of alpha-olefins.
Another object of this invention is to provide a novel and improved method for preparing a catalyst composition.
Another object of this invention is to provide a process for preparing a tetravalent titanium compound and magnesium alkoxide containing catalyst composition wherein the magnesium alkoxide is intimately dispersed in the support.
Another object of this invention is to provide a process for preparing a catalyst composition comprising a magnesium alkoxide wherein the magnesium alkoxide is formed in situ by mixing magnesium with an alcohol to form the alkoxide and agglomeration of the resultant sticky magnesium alkoxide is avoided.
Another object of this invention is to provide a process for preparing a catalyst composition comprising a tetravalent titanium compound and a magnesium alkoxide wherein the magnesium alkoxide is formed by mixing magnesium and alcohol and rapid and complete reaction of the magnesium and alcohol is insured and the precise amount of alcohol can be metered into the reaction mixture.
Other objects, aspects and the several advantages of this invention will be apparent to those skilled in the art upon a study of this disclosure and the appended claims.